Inbreeding is when you allow your dogs to mate father to daughter, brother to sister and mother to son. People allow this happen for various reasons which including the fact that they kept one of the puppies from the litter to breed with, they bought the bitch and dog from the same litter and many other reasons. Inbreeding may sound unethical comparing it to humans but on the medical side, there are numerous implications.
I was called to examine a set of newborn puppies one morning. The owner simply told me she didn’t understand what she was seeing or how to describe it. On arrival, I saw something that made me wonder. I saw about 3 out of the 6 puppies with serious deformations which include cleft lips, limbs without digits and others. The other 3 appeared normal.
The 3 puppies couldn’t breastfeed at all. I prescribed alternative feeding for them but after some days they all died including the healthy looking puppies. I was aware that the puppies were a result of inbreeding but I refused to completely attribute the deformations to that fact because there are other factors that can cause those congenital deformations. I recommended that the female should not be crossed with the brother anymore.
The same bitch was crossed with another male and all the puppies were healthy and survived. This helped me to conclude that inbreeding should be discouraged. I have seen so many cases where inbreeding did not bring out the above deformations so I will consider those puppies as being lucky to be alive.
By the book, inbreeding might bring about the manifestation of undesirable genes. This means that these undesirable genes were there but was not able to express until there is re-introduction by a dog with same parents or the parent which forces the genes to manifest. I don’t want to go into genetics but genetics explains everything. It’s simply reasonable to just advise you not to allow inbreeding than to feed you with genetics to explain why.
The adverse effect of inbreeding can be explained with the genotype in humans where an AS genotype is not advised to have a baby with someone with the same AS genotype because the two S might combine into SS which produces the sickle cell patient. This patient suffers all his life depending on constant medication to stay alive.
Getting away with healthy looking puppies should not be a reason to continue inbreeding. It is better to avoid it in other not to endanger the puppies that are born as a result. It is best practice to mate a bitch with an unrelated dog to avoid the consequences of inbreeding.